Above is one of the pictures of the previous journey from Ipoh back to Kuching. I have taken these photos from the airplane. It was a Sunday evening flight. The cloud has turned its colour to a beautiful warming orange colour.

When the airplane was turning its direction, the other side of the sky looked like this.

I like to take the evening flight, because I can experience the changes of the sky light from bright to dark, at the same time I can see the beautiful clouds. We were sitting on the right side of the airplane and the flight was from West to East, therefore from the window I had to turn my head back a bit to see the cloud near the sun at the West side.

While I was looking at the scenery through the airplane windows, suddenly I noticed that there was another airplane flying in the opposite direction very quickly on another invisible lane on the sky. This was not the first time, I found it twice, one in the 9am morning flight from Kuching to KL, another one was 5pm evening flight from KL to Kuching. I missed both chances to take the photos because when I wanted to switch on my camera, the airplane had gone. The first time I saw the airplane size was quite big, it means both airplane were quite near, but the second time I saw it was a bit smaller.

Hopefully next time, I have got my camera ready, and get the right time to take the photos. I hope that I can take the picture of the airplane and at the same time with a beautiful evening scenery as the background of the picture, that will be the best.

Can you notice what is the different between the pictures of peanuts above? The were actually taken at the same position, only the setting on the camera was different. The F number for first picture was f/2.8, and the second picture was f/8.

Yes, the F number can affect the Depth of Field of the pictures.

“In optics, particularly film and photography, the depth of field (DOF) is the distance in front of and beyond the subject that appears to be in focus.” - Quoted from Wikipedia.

The camera I used only allow me to use the F number from f/2.8 up to f/8, therefore the DOF is still limited. A good lense sometimes can have F number from f/1 up to f/32 or f/38. The F number is actually indicate the aperture of the lense. The smaller the F number, the larger the aperture.

One of the reasons to control the Depth of Field is to emphasis the subject. A good photo will have its subject sharp and the rest of the background blur. That means a shallow Depth of Field allow you to emphasis the subject better.

The other reason why to increase the Depth of Field is to increase the range in focus. It is useful when taking a portrait while want to keep the background scenery clear and sharp. This can be done by increase the F number.

Actually most of the automatic camera by default, have been manufactured in this way so that it produces clearer pictures without the need of focusing. But you cannot reduce the Depth of Field to emphasis a subject on an automatic camera.

Let’s see some other examples of controlling the Depth of Field with the pictures of peanuts.

“hao yi duo mei li de mo li hua…hao yi duo mei li de mo li hua…” This is a very popular Chinese folk song about the Jasmine flower. Jasmine flowers have a very nice scent. One can smell it even though they are not very near to the plant. This breed of Jasmine flower is called the Jasminum Sambac. It looks very much like a white rose but it actually isn’t.

This is how it looks like when all the petals of the Jasmine flower have dried out and fallen out from its bud.

Jasmine flowers are also very popular as the plant that are being produced into tea leaves. The Jasmine tea smells fantastic.

Jasmine flowers are generally white. Their colour and scent give out a clean and refreshing feeling to anyone who goes near them.

I have solved the Rubik’s Cube for the first time in my life.  I didn’t solve it myself, but with the help of a website.  However it is still better than cannot solve it at all.  I am still in the process of learning how to solve it manually.

Nowadays, it is not necessary to solve problems manually.  There are machines, and tools that can make our life easier.  Computer and the Internet are the good examples.  Can you imagine the time when there is no computer, all calculation have to be done manually and human may make mistakes, and to prevent mistakes, more effort is needed to solve a problem.

I have learned how to calculate square root of a number manually instead of using calculator, I learned it from the mathematics text book which was published in 1950’s.  And now, this skill is not included in the school syllabus anymore.  I believe that everybody prefer just to use the calculator to get the answer instead of wasting few minutes of time to calculate the square root of a number.  When I was in secondary school, we were still using the “Mathematics Table” or in Malay we called it “Buku Sifir” to look for the answers for Square root, Sine, Cosine and Log functions.  But now even a form three student is allowed to use the calculator.  I guess may be in the future, students are allowed to bring their notebook for the exams.  And the next generations may not know what “Buku Sifir” is anymore.

Just in case you have forgotten what square root is, Let me explain.

The square root of 9 is 3, because 3 X 3 equals to 9.  This is a simple example, but how about the square root of 2?  It’s not easy to tell.  What is the number that when multiply by itself is equal to 2?  The answer is 1.4142135.

Yes, besides photography, gardening, and enjoying the nature, I’m also interested in Mathematics and logical things.  Rubik’s cute is one of them.  Hopefully I can solved it by myself soon.